Like most nations in South America, Paraguay is faced with a number of environmental challenges. Both of its major biomes (Chaco, Interior Atlantic Forest/lAF) are currently undergoing rapid anthropogenic land cover change. We hypothesize that the rapid anthropogenic land cover change occurring in Paraguay will have a direct impact on ecosystem viability as well as biodiversity and, therefore, will effect rodent-hantavirus ecology. We propose to test this hypothesis by longitudinal monitoring of anthropogenically disturbed and undisturbed sites in the Chaco and IAF. The data will be used to develop predictive models of the relationship between anthropogenic environmental changes and the dynamics of hantaviruses in rodent populations. Furthermore, the data collection and the model building efforts will concentrate on sigmodontine rodents of the three genera: Oligoryzomus, Akodon and Calomys and the hantaviruses that have been identified from each. Our overarching objective requires a multidisciplinary, binational effort. Therefore, this proposal brings together scientists with strengths in mammalogy (Owen, Texas Tech University, TTU), landscape ecology and climatology (Goodin and Hutchinson, Kansas State University, KSU), mathematical modeling (Allen, TTU), human epidemiology (Almiron, Health Sciences Research Institute, IICS in Spanish), computer science (Ranjan, Pontelli, Tran, New Mexico State University, NMSU), and virology (Jonsson, Southern Research Institute). Our specific objectives are: (1) to longitudinally monitor, measure, and model how the distribution and population of rodents and hantaviruses change over time in each biome within disturbed (anthropogenic activity) and undisturbed study sites in the IAF and the Chaco; (2) to develop models of the temporal and spatial dynamics of rodent-virus ecology; and (3) to design and implement a database management system to integrate these types of data for hantaviruses.